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No. 620,960. Patented Mar. l4, I899.

J. PRATT. TYPE WRITING MACHINE.

(Applicatlon filed June 20, 1895. I (No Model.) 4 Sheets-Sheet I.

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No. 620,960. Patented Mar. l4, I899.

J. PRATT. TYPE WRITING MACHINE.

(Application filed June 20, 1895.

4 Sheets-Sheet 2.

{No Model.)

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' No. 620,960. Patented Mar. 14, I899.

J. PRATT.

TYPE -WR|TING MACHINE.

(Application filed June 20, 1895.)

(No Model.) 4 Sheats-S,haet 3.

THE norms PETERS co. womuruou WASHINGTON, my C.

NO. 620,960. Patented Ma'r'. [4,1899.

J. PRATT.

TYPE WRITING MACHINE.

( Application filed June 20, 1895.)

4 Sheets-Sheet 4,

(No Model.)

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"m: NORRIS PETERS 00.. PHOTO-UTHG. WASHINGTON, D c.-

UNITED STATES PATENT OFFICE.

JOHN PRATT, OF NEW YORK, N. Y., ASSIGNOR TO THE HAMMOND TYPE- WRI'IERCOMPANY, OF SAME PLACE.

TYPE-WRITING MACH'I N E.

SPECIFICATION forming part of Letters Patent No. 620,960, dated March14, 1899.

Application filed June 20,1895. $erial No. 553 ,460. (No model.)

To all whom it may concern:

Be it known that I, JOHN PRATT, a citizen of the United States, residingat New York, (Brooklyn,) in the county of Kings and State of New York,have invented a new and useful Type-WVriting Machine, of which thefollowing is a specification.

My invention relates to improvements in type-writing machines of theclass in which all the types are in one type -carrier, and moreespeciallyin the line of my United States and English patents of 1868and 1869, respectively. I

The objects of my improvements are speed, accuracy, uniform touch forall the keys,manifolding, and simplicity, cheapness, and durability ofconstruction. I attain these objects by the mechanism illustrated in theaccompanying drawings, of which Figure 1 is a plan of the entiremachine; Fig. 2, a plan of the machine with papercarriage, spools, andtype-plate removed; Fig. 3, a vertical lateral section of the machinealong the line 03 w of plan 1; Fig. 4., a rear elevation of same; Fig.5, a vertical longitudinal section along the line y y of plan 1; Fig. 6,a partial longitudinal elevation of left side of machine; Fig. 7, a rearview of stopplate and guide; Fig. 8, a view of stop-plate and stop-armsin contact; Fig. 9, a view of type-plate, and Fig. 10 ofreversing-mechanism.

Similar letters and numerals refer to like parts throughout the severalviews.

A is a wooden case, to which is secured the metal base-frame B, to whichis fixed all the mechanism except some parts relating to feed. Bar N issecured to standards M.

The types are arranged in horizontal rows on the face of a rectangularplate D, which may be of thin metal or of celluloid, parchment, orsimilar substance, and in case of metal may be stamped thereon or formedof electros. In case celluloid is used the type is preferably of rubberand may be slit at the lower end to receive the margin of celluloid andsecured with cement, as shown at 19, Fig. 9. 'Thetypes are slit'apart invertical rows of three each, preferably, and are arranged, preferably,with the lower case in the upperrow, capitals inthe middle, and thefigures and other signs in the lowermost row. The separation of the typetriplets is intended to secure the clean impression, especially inmanifolding, of the separate types, free from smudgings of adjacenttypes, and the plate is made flexible in order that each slat whenstruck by the hammer may be driven a little beyond the vertical plane ofthe type-plate. In order that the work may be seen as done, thetype-plate is set about a quarter-inch from the platen and is movednearly in contact .with the platen before impressed, as shownhereinafter.

The type-plate is curved at each end into short cylinders, through whichpasses a guiderod W, on which it slides laterally. This rod rests inholes in the upper ends of the sides 0c of an H -shaped frame 00 102,where it is confined by the thin strips 202 203, made flexible, so thatthe rod, and with it the type, maybe instantly removed for cleaning. Thetypeplate has a prolongation which enters a slot 300 in a plate 201, bywhich it is held in a vertical position. This prolongation is slotted at2 and forms a yoke to receive a pin '74, fixed in the upper end of armg, forming a prolongation of stop-arms f and secured therewith to hub 82of shaft 0, pivoted in bars 105 106, framed into bars 73, secured to barN. 011 the obverse face of said hub is fixed driverarms e, formed, likethe stop-arms, of one piece. Driver-levers I, journaled on brackets O,secured to standards M, traverse over the key-levers, nearly meeting atthe middle of keyboard. These driver-levers oscillate the shaft 0 andarm g, the one to the right and the other to the left, and by means ofthepin 74 move type-plate to and fro on its guide-rod, the slot intype-plate permitting-the circular movement of the pin. The nearer agiven key-lever is to the fulcrum of its driver-lever the greater itsmovement, and it is the relative position of these that determines thedegree of movement of a given type. A little over half the movement ofthe driver-levers is waste in order that either one may be in positionto operate its driver-arm from the extreme limit of its previousmovement, for if a given lever rested normally immediately under itsdriver-arm the type-plate would have to return to its initial positionbefore the next key could be struck. So machines of this class have thedriver initially out of the field of movement of the driver-arms 0rgear-arms, as the case may be; otherwise the movement would be lockedboth right and left, and to allow the type-bearer to return to itsinitial position the previously-struck key must be allowed to rise toits initial position, and this takes time.

The reversing mechanism consists of a lug 2', which is a lightthree-sided rectangular frame pivoted to frame-lever K Pand having theupper ends of its fingers bent over the reversing-arms d, mounted on theshaft 0. \Vhen the said frame-lever is lifted by a key-lever, thetype-plate is freed from any resistance, but when the lever drops backto its place the lug reverses it to initial position. The novelty ofthis reversing mechanism is that no special reversing-spring is employedas in all other machines of this class, and the key-touch, as regardsthis movement, is sub stantially the same for all the key-levers. It isthe weight of P in the frame that does this work while reversing theescapement and hammer, as shown hereinafter.

The mechanism for stopping the type-plate at the impression positionconsists of framelever J Q, consisting of shaft J, side arms 15,

a wooden bar Q, having regulator-screws 16 therein, a middle arm 14, anda stop-frame 13, resting in a notch of arm 14. Said frame 13 is slottedand guided by a projection 209 on bar 106. (See Fig. 7.) Frame 13 isflanged on both sides, as shown, and one or the other of said flangesmoves counter to its stop-arm and opposes and stops its downward mover;

Frame-lever The degree,

ment and so stops type-plate.

J Q, is centered in standards R. of its movement is regulated byadjustingpins 16, and that movement is greater in proportion as themovement of a driver-lever is less. over a corresponding key-lever andthe nearer a screw in initial position is to its key-lever the sooner,therefore, said key-lever will operate the frame-lever J Q and thesooner the'latter stops the type-plate. The adjusting-screws may be setin the key-levers instead of the frame-lever. Usually the driver-leversoperate as such but in very rapid manipulation it often happens that thestop-lever acts as the.

driver'lever and the d river-lever as the stop-leyer, forin such casethe key-lever acts before the reversing-lug has time to returntype-plate to initial position, and then the type-plate, instead ofmoving as usual to the lefte. 9., when impelled by a right-handdriverlevermoves to the right from a previous longer movement in theopposite direction. Properly, therefore, the driver-levers should benamed driver stop-levers and the stop-levers stop driver-levers fromtheir double function, and so of their adjuncts, andlshall so designatethem in the claims. I dwell on The regulator-screws are severally setthis as anovel feature of this invention, since in all other machines ofthis class the righthand and left-hand series of key-levers impartmotion only in one direction and the re versing-sprin g and mechanism isindispensable, the machine being inoperative without it. In this thereversing-1n g is not necessary, but is used only as a subsidiarydevice, the mechanism in many positions moving the type from the lastpreceding position, and in all cases may do so. All this tends toincrement of speed.

The paper carriage consists of two end plates G, framed together by bar39, guiderod 37, bail 94, large rollerE, pressed in contact with smallroller F, and axled in said plates. Other parts thereof are paper-guidescroll 86, secured to bar 39 by brackets l], antifriction-rollers 40,axled on said bar 39, presser-roller frame 36, carrying rollers 35, anda guide-plate 21, consisting of thin sheet metal stretched between endplates just above small roller. Other parts will be described in showinginterlinear mechanism. The paper is introduced between large roller andscroll 86, which guides the upper margin to the lips of the rollers.Large roller is then rotated and the paper moves in contact with guide21 and then presserroller frame is lifted and dropped upon it to hold itsmoothly against the large roller.

The carriage-way frame consists of a swingshaft- T and a rail U, rivetedtogether by arms Y. The rollers 40 travel on rail U, being securedthereto by brackets 41, which are perforated so as to slide on saidrail. These perforations are open, as shown, to allow the arms Y to passthrough. Shaft T is pivoted to standards S, and the frame is held ininitial position byspiral spring 89. A set-screw collar 42 stopscarriage at any desired point by coming in contact with one of brackets41.

The carriage is supported vertically by a vertical slot in standard 17,wherein rod 37 moves laterally for line-feed and Vertically, as willhereinafter be described, for another purpose.

The line-feed mechanism consists of the ratchet-bar 63, secured toswing-frame 62, hinged to end plates G at (34, having a perforatedprojection for fastening pulleycord, pulley-wheel V, journaled instandards 68 and operated by spring tensioned by disk 70 and screw 71,pressing against same. The swing-frame is hinged to paper-carriage so asto allow the feed to be operated at anyvertical position of thecarriage. The feed is accomplished by means of escapement mechanismgeared with ratchet-bar. This consists of the frame-lever K P, operatedby all the key-levers severally, arm 56, secured to a sleeve 57, mountedon shaft K and geared with a hanger 55, pivoted to arm 51, mounted onshaft 52, stepped in standard 17. The sleeve has also an arm 58 restingon bar P of lever K P. Sleeve 57 fits shaft K loosely and arm 58 restson P is also actuated by said leverK P. Secured to standard 17isabracket 47, having two notches in which reciprocate detents 50 and48, pivoted to arm 51 on opposite sides of shaft 52, whereon said armosoillates. Initially detent 48 is geared with the ratchet through nib49, its slot in bracket 47 allowing lateral play corresponding to thedistance of one escapement movement. Spring 97, connecting the twodetents, causes detent 48 to resume initial position after retractionfrom ratchet-bar. Detent 48 has a nib 49 pivoted thereto, which allowsthe ratchet free reverse movement when the carriage is pushed back for afresh line of print. The reverse movementof scapement is made by weightof bar P. The large forward movement of carriage is made by liftingswingframe 62. Space-key lever 60 has an upward limb 61 which restsagainst arm 58, mounted, as has been said, on sleeve 57. The spacekeythrough these parts actuates the escapement independently of the lever KP without moving it and without disturbing the impression mechanism.Spring 115 reverses the arm 58, and so the escapement for spaces, beingtensioned by collar 116 just enough for this, but not enough to liftlever K P.

The page -feed mechanism consists of ratchet-wheel 23, secured to end ofroller E, pawl 24, hinged on arm 25, which is a prolongation of a disk,a slotted lever-arm 27, straddling said pawl, a shaft 28, whereon ismounted said arm, a reversing-spring 29, tensioned by set-screw collar30, a thumb-plate 31, slotted at its lower end to receive anadjustingscrew pin 32, stepped in end plate of carriage and bearing anadjusting-nut 33; also, of friction-washer 87 and collar 88. Initiallythe pawl is lifted by spring 29 out of engagement with theratchet-wheel, so that the large roll may be revolved either way freelywithout lifting a latch. A pin 26 on arm 25 limits the movement of pawland causes 25 to move with it. The reverse movement of arm 25 is limitedby a pin 206, fixed in end plate G. The page-feed is operated bypressing the thumbplate in pushing back the carriage. This brings thepawl into gear with the ratchetwheel, because the friction of the arm 25against the friction-washer is greater than the friction of the pawl inits bearing. Then the roller E is moved a distance determined by theadjusting-nut 33.

The impression mechanism consists of a hammer L, having the facevertically prolonged to cover the field of impression, connecting-rod 8,geared with arm 7 on end of hammer-shaft and with arm 9 on shaft K oflever K P. Since it is difficult to time the hammer-stroke so as tofollow and not precede the stop of the type-plate, I employ a mechanismto slightly delay the stroke. This consists of mounting arm 9 on shaft Kso that it may turn freely thereon. A set-screw collar has a pin 10passing behind arm 9. A spring 11, tensioned by set-screw collar 12,

'ness of the stroke.

presses arm 9 against pin 10. Now when a key is struck the arm 9 propelsthe hammer through the resistance of the spring, which yields the morein proportion to the sudden- The resistance of the spring is regulatedby the tension-collar. The hammer-shaft is journaled in projections ofbars 73.

In its initial vertical position the paper-carriage is so adjusted thatthe upper part of the hammer-face strikes the outer row of types againstthe large roller. Since the type-plate cannot be raised to bring thesupplementary type rows into the field of impression without changingthe relative positions of the type moving and stopping mechanism, it isnecessary to lower the paper-carriage. anism for this purpose consistsof the carriage-way frame, already described, arm 100 on the left end ofrail U, hangers 45 and 46, secured to shaft 72 and forming therewith atoggle-joint, shifting-keys y y, fixed to said shaft and having theirmotions regulated and limited by adj usting-screws 107. A pressure oneither key lowers the carriage by flexing the joint. the screw on thatside stops the platen at the capitals row of type. If the left-hand keyis pressed, its screw stops it at figures and signs. Reversing-spring 89brings back the carriage to initial position. During this verticalmovement of the paper-carriage the ratchet bar or rack 63, secured toswing-frame 62, rests on bracket 47, while only its hinge connectionwith paper-carriage shifts therewith. Guiderod 37 descends in slot ofbar 17.

The ribbon is wound on spools p and feeds from one to the other. Thespools are mounted on shafts r, the spool on the right hand turning onbut not with it. That on the lefthand shaft is geared therewith by meansof a pin is and a disk 108, having perforations to receive it. The feedconsists of an ordinary ratchet-wheel s, pawl 25, pawl-lever u,connecting-rod 103, hinged to lever '10, and arm 104 of shaft K. Thelift of frame-lever K P operates the feed. The spools have each a pin ison obverse sides, and the ribbon is reversed by interchanging spools,which hasthe advantage of presenting a fresh margin thereof andincreasing its durability. The spools are fitted loosely on the shaft,so as to be easily lifted ofi to renew ribbon.

' Normally, as has been said, the type-plate .is held some distance fromthe platen, but it is moved nearly in contact therewith before thehammer strikes it. For this purpose the 1 H -fram e, consisting of twouprights ac, framed by cross-bar 102, is hinged at 210 to brackets 211,secured to bar N. A connecting-rod 212 is pivoted to a boss 213 on saidupright 00 and also to an arm 214 on shaft K. Shaft K moves the saidframe and the type-plate 'sim ultaneously with the hammer. The frame P,shaft K, and arm 214 constitute abell-crank lever for operating theH-frame through the link 212. The ribbon 202, guided and sup- The mech-If the right-hand key is pressed,

ported by slits in the plates 203 terminating uprights 00, is moved toand fro with typeplate, so that the last letter of line of print may beseen after each impression.

The key-levers operating all rest in the slots in the plates a onfulcraat the bottom of slots cut shallow where used as fulcra or else onseparate fulcra b, according to what bank a given key may belong to.There are preferably four banks of keys with fulcra so arranged as toequalize leverage.

Having thus described my invention and the mode of operating the same, Iclaim- 1. In a type-writer, the combination with the platen, of atype-plate having the type arranged on the side nearest the platen, apivoted frame supporting said .plate in front of the platen, abell-crank rock-lever having one arm bearing upon the key-levers, andadapted to be operated by the same, and a link pivoled to the oppositearm of said lever and to said frame respectively, whereby the frame andplate are rocked toward and away from the platen, as set forth.

2. In a type-writer, the combination with the platen, of a type-platehaving the type arranged on the side nearest the platen, a pivoted framesupporting said plate in front of the platen, a rock-lever adapted to beoper-. ated by the key-levers, a link connecting said frame androck-lever, the hammer having its striking-face in front of thetype-plate, and

, its operating-arm connected with the shaft of the rock-lever, all asset forth.

3. In a type-writer, the combination with the platen, of the flattype-plate having the type arranged on the side nearest the platen, apivoted frame supporting said plate in front of the platen, and asupport in said frame and between the plate and the platen for theinkingribbon, a bell-crank rock-lever having one arm bearing upon thekey-levers and adapted to be operated by the same, and a link pivoted tothe opposite arm of said lever, and to said frame respectively, all asset forth.

4. In a type-writer, the combination with the platen, of a type-platehaving the type arranged on the side nearest the platen, and supportedon a pivoted frame in front of the platen, a rock-lever adapted tooperate said frame, and be operated by the key-levers, the hammer havingits striking-face in front of the type-plate, a spring secured to therocklever and bearing upon the hammer-operating arm, all as and for thepurposes set forth.

5. In a type-writer, the combination with the type-plate supportedloosely on a horizontal guide, and having a downwardly-projectingyoke,adriver-lever having its two arms extending laterally on oppositesides of its fulcrum, and having an upwardly-extending arm engaging withthe yoke of'the type-plate, two sets of key-levers and intermediatemechanism whereby the operation of said two sets of levers will causethe two driver-arms to raise respectively and slide the type-platelaterally in both directions, all as set forth.

6. ha type-writer, the combination with the type-plate supported looselyon a horizontal guide and having a downwardly-pro posite sides of itsfulcrum, an arm extending upward from said levers and engaging with theyoke of the type-plate, two sets of key levers, and intermediatemechanism for raising the two driver-arms respectively, and mechanismfor stopping the movement of the descending stop-arm, all as and for thepurposes set forth.

8. In a type-writer, the combination with the type-plate supportedloosely on a horizontal guide and having a downwardly-projecting yoke, adriver and a stop-lever both hav ing their arms extending laterally onopposite sides of its fulcrum an arm extending upward from said leversand engaging with the yoke of the type-plate, two sets of key-levers andintermediate mechanism for raising the two driverarms respectively, anda verticallymovable frame raised by the action of the keylevers forcoming in contact with one of the descending stop-arms and thus limitingits descent, all as and for the purposes set forth.

9. In a type-writer, the combination with the type-plate supportedloosely on a horizontal guide and having a downwardly-projecting yoke, adriven lever having its two arms extending on opposite sides'of itsfulcrum,and having an upwardly-extending arm engaging with the yoke ofthe type-plate, two sets of key-levers, two transverse arms pivoted tothe machine-frame, and extending over the two sets of type-leversrespectively, and said two arms adapted to raise the two driver-armsrespectively,all as and for the purposes set forth.

10. In a type-writer, the combination with the type-plate supportedloosely on a horizontal guide and having adownwardly-projecting yoke, arocking lever having its two arms extending on opposite sides of itsfulcrum,and having an upwardly-extending arm engaging with the yoke ofthe type-plate, a frame adapted to be raised and depressed by thekey-levers, and having two vertical arms with bent ends overlapping thetwo rocking arms respectively,all as and for the purposes set forth.

11. In a type-writer, the paper-carriage, in combination with a springswing-frame supporting said carriage and the action of the springtending to force the frame upward, a toggle-joint the upper arm of whichis connected with said carriage, the lower arm be- IlO ing secured to arock-shaft, a rock-lever on said shaft, and stops arranged at difl'erent13. A type-plate for a type-writer, consisting of a series of rubber orother flexible strips having the type upon one side, and said stripsarranged side by side, and attached to a 10ngitndinal strip of celluloidor similar material, by slits and cement, and a rigid connection withsaid strip, whereby the plate may be moved operatively on the machine,all as set forth.

JOHN PRATT.

Witnesses:

L. HOLLOWAY, M. C. PINCKNEY,

